Question

1.5 bell ringer: proof of earth’s formation and layers

1. what is the primary reason scientists can determine that earths outer core is liquid?
2. which layer of earth is considered semi - fluid and allows tectonic plates to move?
3. what important information do carbonaceous chondrites provide about earth?
4. what evidence suggests that earth had liquid water early in its history?
5. what makes the asthenosphere different from the lithosphere?

Explanation:

1. S - waves cannot travel through liquids. Since S - waves disappear when they reach the outer core, scientists infer it is liquid.
2. The asthenosphere is semi - fluid and allows tectonic plates to move due to its plastic - like behavior.
3. Carbonaceous chondrites are primitive meteorites. They provide information about the composition of the early solar system and by extension, the early Earth as they are thought to be remnants of the material that formed the planets.
4. Sedimentary rocks like conglomerates and fossilized remains of early life forms that require water for their formation suggest the presence of liquid water early in Earth's history.
5. The lithosphere is rigid and brittle, while the asthenosphere is semi - fluid and can flow slowly over long periods, which is why tectonic plates move on the asthenosphere.

Answer:

1. S - waves cannot pass through it.
2. Asthenosphere.
3. Information about early Earth's composition.
4. Sedimentary rock evidence and fossil evidence.
5. The asthenosphere is semi - fluid and the lithosphere is rigid.